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INFO: rcu detected stall in batadv_nc_worker

Status: upstream: reported C repro on 2023/06/13 20:27
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+42b636738d776704a740@syzkaller.appspotmail.com
First crash: 811d, last: 2d02h
Fix commit to backport (bisect log) :
tree: upstream
commit 5f6bd380c7bdbe10f7b4e8ddcceed60ce0714c6d
Author: Peter Zijlstra <peterz@infradead.org>
Date: Mon May 27 12:06:55 2024 +0000

  sched/rt: Remove default bandwidth control

  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/03/16 linux-5.15.y (ToT) 0c935c049b5c C [report] INFO: rcu detected stall in corrupted
2025/03/16 upstream (ToT) 31d7109a19f6 C Didn't crash
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in batadv_nc_worker origin:lts-only 1 C done 181 54m 788d 0/3 upstream: reported C repro on 2023/07/06 06:16
upstream INFO: rcu detected stall in batadv_nc_worker cgroups mm 1 7 2098d 2100d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in batadv_nc_worker (2) mm 1 4 2063d 2063d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in batadv_nc_worker (3) batman 1 C done inconclusive 578 4d05h 1796d 0/29 upstream: reported C repro on 2020/10/01 10:35
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/07/31 07:51 7h53m fix candidate upstream OK (1) job log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P1228/1:b..l
	(detected by 1, t=10502 jiffies, g=6901, q=112)
task:kworker/u4:3    state:R  running task     stack:25000 pid: 1228 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline]
RIP: 0010:lock_acquire+0xc6/0x3f0 kernel/locking/lockdep.c:5594
Code: 08 0f 83 8c 01 00 00 44 89 f0 c1 e8 06 48 8d 3c c5 a8 8c 69 8d be 08 00 00 00 e8 b5 39 60 00 44 89 f0 48 0f a3 05 e2 93 0d 0c <73> 0d e8 73 b6 07 00 84 c0 0f 84 17 02 00 00 48 c7 c0 44 c0 69 8d
RSP: 0018:ffffc90004d17aa0 EFLAGS: 00000257
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815bf8bb
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d698ca8
RBP: ffffc90004d17bc0 R08: dffffc0000000000 R09: fffffbfff1ad3196
R10: fffffbfff1ad3196 R11: 1ffffffff1ad3195 R12: ffffffff8c11c460
R13: 1ffff920009a2f60 R14: 0000000000000001 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0xc9/0x5c0 net/batman-adv/network-coding.c:723
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10527 jiffies! g6901 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=7812
rcu: rcu_preempt kthread starved for 10528 jiffies! g6901 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:27584 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 4427 Comm: syz.2.19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 1d aa f7 48 89 df e8 56 f2 aa f7 e8 d1 8c cb f7 fb bf 01 00 00 00 <e8> a6 15 9f f7 65 8b 05 a7 13 50 76 85 c0 74 02 5b c3 e8 54 1e 4e
RSP: 0018:ffffc9000386fbc0 EFLAGS: 00000282
RAX: 7bdfa897fc6b7b00 RBX: ffff88807423ae40 RCX: 7bdfa897fc6b7b00
RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: 0000000000000001
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100e8475c9
R10: ffffed100e8475c9 R11: 1ffff1100e8475c8 R12: ffff88807423ae40
R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x11d6/0x12c0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6b30d6dbe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe927000f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f6b30fa4fa0 RCX: 00007f6b30d6dbe9
RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6b30df0e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b30fa4fa0 R14: 00007f6b30fa4fa0 R15: 0000000000000004
 </TASK>

Crashes (228):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/31 02:37 linux-5.15.y 01879f56bdde 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/30 15:04 linux-5.15.y 01879f56bdde 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/02/13 09:32 linux-5.15.y c16c81c81336 b27c2402 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/30 23:56 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/30 20:47 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/30 05:51 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/21 21:49 linux-5.15.y c79648372d02 3e79b825 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in batadv_nc_worker
2025/08/17 22:57 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/16 17:25 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in batadv_nc_worker
2025/08/16 13:43 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/13 10:51 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/10 18:52 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/07 16:59 linux-5.15.y c79648372d02 04cffc22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/07 02:59 linux-5.15.y c79648372d02 9a42d6b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/31 23:26 linux-5.15.y c79648372d02 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/28 06:38 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/23 13:37 linux-5.15.y c79648372d02 e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/18 19:38 linux-5.15.y c79648372d02 88248e14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/13 05:48 linux-5.15.y 2f693b607545 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/11 01:28 linux-5.15.y 2f693b607545 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/08 16:55 linux-5.15.y 3dea0e7f549e 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/03 16:29 linux-5.15.y 3dea0e7f549e 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/02 21:55 linux-5.15.y 3dea0e7f549e bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/07/01 01:28 linux-5.15.y 3dea0e7f549e 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/28 23:38 linux-5.15.y 3dea0e7f549e fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/28 02:27 linux-5.15.y 3dea0e7f549e fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/24 16:32 linux-5.15.y 1c700860e8bc e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/20 07:19 linux-5.15.y 1c700860e8bc ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/10 00:54 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/09 09:59 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/08 23:26 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/08 13:08 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/08 07:51 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/06 14:34 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/06 06:59 linux-5.15.y 1c700860e8bc 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/03 08:55 linux-5.15.y 98f47d0e9b8c a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/03 07:21 linux-5.15.y 98f47d0e9b8c a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/01 13:21 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/06/01 02:35 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/28 17:45 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/24 07:20 linux-5.15.y 98f47d0e9b8c ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/23 11:36 linux-5.15.y 98f47d0e9b8c fa44301a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/22 05:25 linux-5.15.y a68c15152131 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/21 10:37 linux-5.15.y a68c15152131 b47f9e02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/19 23:49 linux-5.15.y a68c15152131 b84f0537 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/18 15:01 linux-5.15.y a68c15152131 f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/14 00:32 linux-5.15.y 3b8db0e4f263 7344edeb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/09 04:33 linux-5.15.y 16fdf2c7111b bb813bcc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/05/05 19:49 linux-5.15.y 16fdf2c7111b 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/04/30 15:32 linux-5.15.y f7347f400572 85a5a23f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/04/30 05:08 linux-5.15.y f7347f400572 85a5a23f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/05/18 17:45 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in batadv_nc_worker
2023/06/13 20:26 linux-5.15.y 7349e40704a0 d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
* Struck through repros no longer work on HEAD.